69 research outputs found
WISDOM Project II: Molecular gas measurement of the supermassive black hole mass in NGC4697
As part of the mm-Wave Interferometric Survey of Dark Object Masses (WISDOM) project, we present an estimate of the mass of the supermassive black hole (SMBH) in the nearby fast-rotating early-type galaxy NGC 4697. This estimate is based on Atacama Large Millimeter/submillimeter Array (ALMA) cycle-3 observations of the 12CO(2–1) emission line with a linear resolution of 29 pc (0.53 arcsec). We find that NGC 4697 hosts a small relaxed central molecular gas disc with a mass of 1.6 × 107 M⊙, co-spatial with the obscuring dust disc visible in optical Hubble Space Telescope imaging. We also resolve thermal 1 mm continuum emission from the dust in this disc. NGC 4697 is found to have a very low molecular gas velocity dispersion, σgas = 1.65
+0.68−0.65
−0.65+0.68
km s−1. This seems to be partially because the giant molecular cloud mass function is not fully sampled, but other mechanisms such as chemical differentiation in a hard radiation field or morphological quenching also seem to be required. We detect a Keplerian increase of the rotation of the molecular gas in the very centre of NGC 4697, and use forward modelling of the ALMA data cube in a Bayesian framework with the KINematic Molecular Simulation (KINMS) code to estimate an SMBH mass of (1.3
+0.18−0.17
−0.17+0.18
) × 108 M⊙ and an i-band mass-to-light ratio of 2.14
+0.04−0.05
−0.05+0.04
M⊙/L⊙ (at the 99 per cent confidence level). Our estimate of the SMBH mass is entirely consistent with previous measurements from stellar kinematics. This increases confidence in the growing number of SMBH mass estimates being obtained in the ALMA era
AGN X-ray irradiation of CO gas in NGC 2110 revealed by and ALMA
We report spatial distributions of the Fe-K line at 6.4 keV and the
CO( = 2--1) line at 230.538 GHz in NGC 2110, which are respectively revealed
by and ALMA at 0.5 arcsec. A 6.2--6.5
keV-to-3.0--6.0 keV image suggests that the Fe-K emission extends
preferentially in a northwest-to-southeast direction out to 3 arcsec, or
500 pc, on each side. Spatially-resolved spectral analyses support this by
finding significant Fe-K emission lines only in northwest and southeast
regions. Moreover, their equivalent widths are found 1.5 keV, indicative
for the fluorescence by nuclear X-ray irradiation as the physical origin. By
contrast, CO( = 2--1) emission is weak therein. For quantitative discussion,
we derive ionization parameters by following an X-ray dominated region (XDR)
model. We then find them high enough to interpret the weakness as the result of
X-ray dissociation of CO and/or H. Another possibility also remains that CO
molecules follow a super-thermal distribution, resulting in brighter emission
in higher- lines. Further follow-up observations are encouraged to draw a
conclusion on what predominantly changes the inter-stellar matter properties,
and whether the X-ray irradiation eventually affects the surrounding star
formation as an AGN feedback.Comment: 15 pages, 11 figures, 3 tables. Accepted for publication in Ap
The ALMA Discovery of the Rotating Disk and Fast Outflow of Cold Molecular Gas in NGC 1275
We present ALMA Band 6 observations of the CO(2-1), HCN(3-2), and
HCO(3-2) lines in the nearby radio galaxy / brightest cluster galaxy
(BCG) of NGC 1275 with the spatial resolution of pc. In the previous
observations, CO(2-1) emission was detected as radial filaments lying in the
east-west direction. We resolved the inner filament and found that the filament
cannot be represented by a simple infalling stream both morphologically and
kinematically. The observed complex nature of the filament resembles the cold
gas structure predicted by recent numerical simulations of cold chaotic
accretion. A crude estimate suggests that the accretion rate of the cold gas
can be higher than that of hot gas. Within the central 100 pc, we detected a
rotational disk of the molecular gas whose mass is \sim10^{8} M_{\sun}. This
is the first evidence of the presence of massive cold gas disk on this spatial
scale for BCGs. The disk rotation axis is approximately consistent with the
axis of the radio jet on subpc scales. This probably suggests that the cold gas
disk is physically connected to the innermost accretion disk which is
responsible for jet launching. We also detected absorption features in the
HCN(3-2) and HCO(3-2) spectra against the radio continuum emission mostly
radiated by -pc size jet. The absorption features are blue-shifted
from the systemic velocity by 300-600~km~s, which suggests the
presence of outflowing gas from the active galactic nucleus (AGN). We discuss
the relation of the AGN feeding with cold accretion, the origin of blue-shifted
absorption, and estimate of black hole mass using the molecular gas dynamics.Comment: Version 2 (accepted version). 18 pages, 16 figures. Accepted for
publication in Ap
ALMA 0.02"-resolution observations reveal HCN-abundance-enhanced counter-rotating and outflowing dense molecular gas at the NGC 1068 nucleus
We present ALMA ~0.02"-resolution observations of the nucleus of the nearby
(~14 Mpc) type-2 AGN NGC 1068 at HCN/HCO+/HNC J=3-2 lines, as well as at their
13C isotopologue and vibrationally excited lines, to scrutinize the
morphological/dynamical/chemical/physical properties of dense molecular gas in
the putative dusty molecular torus around a mass-accreting supermassive black
hole. We confirm almost east-west-oriented dense molecular gas emission both
morphologically and dynamically, which we regard as coming from the torus.
Bright emission is compact (<3 pc), and low-surface-brightness emission extends
out to 5-7 pc. These dense molecular gas properties are not symmetric between
the eastern and western torus. The HCN J=3-2 emission is stronger than the HCO+
J=3-2 emission within the ~7 pc torus region, with an estimated dense molecular
mass of (0.4-1.0)x10^6Msun. We interpret that HCN abundance is enhanced in the
torus. We detect signatures of outflowing dense molecular gas and a
vibrationally excited HCN J=3-2 line. Finally, we find that in the innermost
(<1 pc) part of the torus, the dense molecular line rotation velocity, relative
to the systemic velocity, is the opposite of that in the outer (>2 pc) part, in
both the eastern and western torus. We prefer a scenario of counter-rotating
dense molecular gas with innermost almost-Keplerian-rotation and outer slowly
rotating (far below Keplerian) components. Our high-spatial-resolution dense
molecular line data reveal that torus properties of NGC 1068 are much more
complicated than the simple axi-symmetrically rotating torus picture in the
classical AGN unification paradigm.Comment: 45 pages, 20 Figures. Accepted for publication in Ap
WISDOM project - VI. Exploring the relation between supermassive black hole mass and galaxy rotation with molecular gas
Empirical correlations between the masses of supermassive black holes (SMBHs) and properties of their host galaxies are well-established. Among these is the correlation with the flat rotation velocity of each galaxy measured either at a large radius in its rotation curve or via a spatially-integrated emission line width. We propose here the use of the de-projected integrated CO emission line width as an alternative tracer of this rotation velocity, that has already been shown useful for the Tully-Fisher (luminosity-rotation velocity) relation. We investigate the correlation between CO line widths and SMBH masses for two samples of galaxies with dynamical SMBH mass measurements, with respectively spatially-resolved and unresolved CO observations. The tightest correlation is found using the resolved sample of 25 galaxies as log (MBH/M⊙) = (7.5 ± 0.1) + (8.5 ± 0.9)[log (W50/sin i km s−1) − 2.7], where MBH is the central SMBH mass, W50 the full-width at half-maximum of a double-horned emission line profile, and i the inclination of the CO disc. This relation has a total scatter of 0.6 dex, comparable to those of other SMBH mass correlations, and dominated by the intrinsic scatter of 0.5 dex. A tight correlation is also found between the de-projected CO line widths and the stellar velocity dispersions averaged within one effective radius. We apply our correlation to the COLD GASS sample to estimate the local SMBH mass function
The opaque heart of the galaxy IC 860: Analogous protostellar, kinematics, morphology, and chemistry
Compact Obscured Nuclei (CONs) account for a significant fraction of the population of luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs). These galaxy nuclei are compact, with radii of 10-100 pc, with large optical depths at submm and far-infrared wavelengths, and characterized by vibrationally excited HCN emission. It is not known what powers the large luminosities of the CON host galaxies because of the extreme optical depths towards their nuclei. CONs represent an extreme phase of nuclear growth, hiding either a rapidly accreting supermassive black hole or an abnormal mode of star formation. Regardless of their power source, the CONs allow us to investigate the processes of nuclear growth in galaxies. Here we apply principal component analysis (PCA) tomography to high-resolution (000:06) ALMA observations at frequencies 245 to 265 GHz of the nearby CON (59 Mpc) IC 860. PCA is a technique to unveil correlation in the data parameter space, and we apply it to explore the morphological and chemical properties of species in our dataset. The leading principal components reveal morphological features in molecular emission that suggest a rotating, infalling disk or envelope, and an outflow analogous to those seen in Galactic protostars. One particular molecule of astrochemical interest is methanimine (CH2NH), a precursor to glycine, three transitions of which have been detected towards IC 860.We estimate the average CH2NH column density towards the nucleus of IC 860 to be _1017cm2, with an abundance exceeding 108 relative to molecular hydrogen, using the rotation diagram method and non-LTE radiative transfer models. This CH2NH abundance is consistent with those found in hot cores of molecular clouds in the Milky Way. Our analysis suggests that CONs are an important stage of chemical evolution in galaxies, that are chemically and morphologically similar to Milky Way hot cores
Determinants of life satisfaction among Japanese elderly women attending health care and welfare service facilities
Prolonged life expectancy must be recognized as an excellent achievement of modern medicine, but not all the elderly people are satisfied with their lives. Life satisfaction is a multi-dimensional issue that depends on many objective and subjective characteristics. In this study, we aimed at investigating the factors affecting life satisfaction of 314 elderly Japanese women attending in 28 elderly-care and welfare facilities at Tokushima Prefecture, Japan. Our results indicated that elderly subjects with depression tendencies always show significantly lower degrees of life satisfaction than others who are not depressed (p 0.001) regardless of their cognitive status. Furthermore, elderly women who shared decision for their living place and whose opinions were considered for daily life decisions reported significantly more life satisfaction levels than others. We conclude that elderly life satisfaction is affected by various determinants however, with different influencing weight. Life satisfaction of elderly people, with or without dementia, is greatly affected by their mood status and share in decision making. Avoiding elderly people depressive mood, sharing them in various daily decisions, considering their opinions, and allowing them to decide their elderly-care facility placement are crucial determinants for their life satisfaction and essential for their coping, adaptation, well-being and successful aging
WISDOM Project -- VII. Molecular gas measurement of the supermassive black hole mass in NGC 7052
Supermassive black hole (SMBH) masses can be measured by resolving the
dynamical influences of the SMBHs on spatially-resolved tracers of the central
potentials. Modern long-baseline interferometers have enabled the use of
molecular gas as such a tracer. We present here Atacama Large
Millimeter/submillimeter Array observations of the elliptical galaxy NGC 7052
at 0.11 arcseconds (37 pc) resolution in the 12CO(2-1) line and 1.3mm continuum
emission. This resolution is sufficient to resolve the region in which the
potential is dominated by the SMBH. We forward model these observations, using
a multi-Gaussian expansion of a Hubble Space Telescope F814W image and
spatially-constant mass-to-light ratio to model the stellar mass distribution.
We infer a SMBH mass of and a stellar
I-band mass-to-light ratio of
( confidence intervals). This SMBH mass is significantly larger than
that derived using ionised gas kinematics, which however appear significantly
more kinematically disturbed than the molecular gas. We also show that a
central molecular gas deficit is likely to be the result of tidal disruption of
molecular gas clouds due to the strong gradient in the central gravitational
potential.Comment: 14 pages, 8 figures, accepted for publication in MNRA
Effects of lifestyle habits and eating meals together with the family on the prevalence of obesity among school children in Tokushima, Japan : a cross-sectional questionnaire- based survey
Obesity in children has become a major global public health concern. The prevention of obesity must start from early childhood in order to establish sound lifestyle habits and promote healthy adulthood. In this study, we evaluated factors associated with the prevention of obesity and the development of healthy lifestyle habits in children. A cross-sectional, questionnaire-based survey was performed in elementary and junior high school students in Tokushima Prefecture, Japan, during the summer of 2004. The questionnaire consisted of 30 items such as physique, sleep, eating habits, diet, exercise, free time, and attending after-school lessons. Our study revealed that eating meals as a family every day is associated with a lower rate of obesity as well as getting good lifestyle habits such as eating balanced meals and getting enough sleep. Of the 3,291 students who responded to the questionnaire, 2,688 (81.7%) reported that they eat meals with their family every day. The percentage of students who eat meals with their family every day decreased with increasing school grade, with the lowest percent in the junior high school students. However, the results regarding female junior high school students revealed a marked association between eating meals with the family every day and good lifestyle habits. We recommend that parents and school teaching staff encourage the establishment of sound, healthy lifestyle habits in children from early childhood as an effective measure for the prevention of obesity
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